Search results for "Hf"

Preparation of Highly Clarified Anthocyanin-Enriched Purple Sweet Potato Juices by Membrane Filtration and Optimization of Their Sensorial Properties

2016

The aim of this work was to prepare clarified anthocyanin-enriched juices from purple sweet potatoes (PSP) and to evaluate their sensorial properties, with promising prospect for antioxidant molecules. Four PSP juice samples were prepared and annotated as (1) crude PSP extract, (2) PSP extract followed by microfiltration, (3) by ultrafiltration and (4) by nanofiltration (4). Although anthocyanins retention was observed during the filtration process, PSP microfiltrated juices generated better permeate with compromising between appearance transparency and anthocyanin content. Juice sensory properties (color, flavor, mouthfeel and clarity) were optimized by an L9(34) orthogonal design using PS…

Synthesis, and Molecular Structure Investigations of a New s-Triazine Derivatives Incorporating Pyrazole/Piperidine/Aniline Moieties

2021

In this work, we synthesized two new s-triazine incorporates pyrazole/piperidine/aniline moieties. Molecular structure investigations in the light of X-ray crystallography combined with Hirshfeld and DFT calculations were presented. Intermolecular interactions controlling the molecular packing of 4-(3,5-dimethyl-1H-pyrazol-1-yl)-N-phenyl-6-(piperidin-1-yl)-1,3,5-triazin-2-amine; 5a and N-(4-bromophenyl)-4-(3,5-dimethyl-1H-pyrazol-1-yl)-6-(piperidin-1-yl)-1,3,5-triazin-2-amine; 5b were analyzed using Hirshfeld calculations. The most dominant interactions are the H...H, N...H and H...C contacts in both compounds. The N...H and H...C interactions in 5a and the N...H, Br...H and H...H interacti…

Synthesis and X-ray Crystal Structure of New Substituted 3-4′-Bipyrazole Derivatives. Hirshfeld Analysis, DFT and NBO Studies

2021

A new compounds named 3-4′-bipyrazoles 2 and 3 were synthesized in high chemical yield from a reaction of pyran-2,4-diketone 1 with aryl hydrazines under thermal conditions in MeOH. Compound 2 was unambiguously confirmed by single-crystal X-ray analysis. It crystalizes in a triclinic crystal system and space group P-1. Its crystal structure was found to be in good agreement with the spectral characterizations. With the aid of Hirshfeld calculations, the H…H (54.8–55.3%) and H…C (28.3–29.2%) intermolecular contacts are the most dominant, while the O…H (5.8–6.5%), N…H (3.8–4.6%) and C…C (3.0–4.9%) are less dominant. The compound has a polar nature with a net dipole moment of 6.388 Debye. The …

X-ray Single Crystal Structure, Tautomerism Aspect, DFT, NBO, and Hirshfeld Surface Analysis of a New Schiff Bases Based on 4-Amino-5-Indol-2-yl-1,2,…

2021

Four different new Schiff basses tethered indolyl-triazole-3-thione hybrid were designed and synthesized. X-ray single crystal structure, tautomerism, DFT, NBO and Hirshfeld analysis were explored. X-ray crystallographic investigations with the aid of Hirshfeld calculations were used to analyze the molecular packing of the studied systems. The H···H, H···C, S···H, Br···C, O···H, C···C and N···H interactions are the most important in the molecular packing of 3. In case of 4, the S···H, N···H, S···C and C···C contacts are the most significant. The results obtained from the DFT calculations indicated that the thione tautomer is energetically lower than the thiol one by 13.9545 and 13.7464 kcal…

Harmonicity and minimality of oriented distributions

2004

We consider an oriented distribution as a section of the corresponding Grassmann bundle and, by computing the tension of this map for conveniently chosen metrics, we obtain the conditions which the distribution must satisfy in order to be critical for the functionals related to the volume or the energy of the map. We show that the three-dimensional distribution ofS4m+3 tangent to the quaternionic Hopf fibration defines a harmonic map and a minimal immersion and we extend these results to more general situations coming from 3-Sasakian and quaternionic geometry.

A new polymorphism in the human HFE gene

1999

Significant association of MTHFD1 1958GA single nucleotide polymorphism with nonsyndromic cleft lip and palate in Indian population.

2014

Objectives: Nonsyndromic cleft lip and palate (NSCLP) is genetically distinct from those with syndromic clefts, and accounts for ~70% of cases with Oral clefts. Folate, or vitamin B9, is an essential nutrient in our diet. Allelic variants in genes involved in the folate pathway might be expected to have an impact on risk of oral clefts. Given the key role of methylenetetrahydrofolate dehydrogenase 1 (MTHFD1) in folate metabolism, it would be of significant interest to assess its role in NSCLP etiology. Study Design: The present study aims at examining the association between MTHFD1 1958G>A polymorphism and NSCLP risk by conducting a case-control study in south Indian population. Our sample …

Geochemistry of Zr, Hf, and REE in a wide spectrum of Eh and water composition: The case of Dead Sea Fault system (Israel)

2017

International audience; Along the Jordan Valley-Dead Sea Fault area several natural waters in springs, wells, and catchments occur. The chemical-physical characters of the studied waters allowed for the first time the investigation of the Zr and Hf geochemical behavior, apart from REE, extended to a wide range of Eh, temperature, salinity, and pH conditions. The results of this study indicate that the dissolved Zr and Hf distribution in natural waters is strongly influenced by redox conditions since these in turn drive the deposition of Fe-oxyhydroxides or pyrite. In oxidizing waters saturated or oversaturated in Fe-oxyhydroxides (Group 1), superchondritic Zr/Hf values are measured. On the …

Anomalous Behavior of Zirconium and Hafnium in Volcanic Fumarolic Fluids

2022

The Zirconium and Hafnium concentrations in worldwide fumaroles fed by magmatic fluids reveal that the Zr/Hf ratio is inversely related to the temperature of emission. Lower Zr/Hf ratio values below the chondritic signature are found in fluids having the highest temperature while super-chondritic Zr/Hf ratio values are found in lower temperatures. Sub-chondritic values of the Zr/Hf ratio may be related to larger volatility of Hf-chloride gas species with respect to Zr-Cl gas species, while super-chondritic ratios may correspond to fluid-rock processes resulting from cooling of uprising magmatic fluids. We propose that subchondritic Zr/Hf ratio values in fumaroles associated with high temper…

Estudo sobre o Global Report Initiative de empresas de energia elétrica dos Estados Unidos, do Brasil e da Espanha no período de 1999 a 2010

2013

Para atender às demandas sociais e organizacionais, vários instrumentos têm surgido para auxiliar o processo de geração de informações ambientais, entre eles o Global Reporting Initiative (GRI). Desde 1999, o GRI vem auxiliando as empresas a medirem e comunicarem seu desempenho econômico, ambiental e social. Sua consolidação ao longo da década de 2000 tornou-o um instrumento de grande aceitação pelas organizações e pela sociedade e, como consequência, tornou-se foco de estudos científicos sobre sustentabilidade (econômica, social e ambiental) nas organizações. Neste contexto, emerge a pergunta da atual pesquisa: Qual o perfil das empresas do setor elétrico listadas no GRI? Para responder a …